Mr Rowley, the police national head of counter-terrorism, said: “It may seem blindingly obvious, but some people don’t run, they will duck down where they are, do all sorts of different things in the panic.

“So let’s be really clear — run as far away as possible and when you can’t run any further, hide, and then call the police because we’ve got the people, the resources, the firearms to deal with it.

“It’s very straightforward.

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The UK’s official terror threat has been at 'severe' for almost two years

PA:Press Association

Met commissioner Bernard Hogan-Howe says an attack on Britain is a matter of 'when, not if'

“Every Londoner can help the fight against terrorism, whether it’s being more prepared personally or at work or if you are suspicious about something or someone.

“If you see someone acting suspiciously near where you work then contact us straight away, whether you are working in Canary Wharf or the local high street.

“We say to the public, trust your instincts and pick up the phone to us.”

He added that scores of people are being “drawn back” from extremism every month as authorities mount a huge effort to contain the terrorist threat in the UK.

Counter-terror police receive more than 30 calls a day about suspicious activity from members of the public.

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Counter-terror police receive more than 30 calls a day about suspicious activity from members of the public

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Earlier this year it emerged that seven plots to attack the UK had been disrupted in the previous 18 months

Corbis

Mr Rowley's appeal follows a spate of deadly Islamic State attacks in France, Belgium and Germany

Mr Rowley said: “We are resolving maybe 60 or 70 cases a month, of which about a sixth of those referrals come from the public.

“We are drawing people back from a path towards extremism through partnership activity.

“Even if you take the view that 90 per cent of those people may have self-treated or not gone on to become terrorists, that is still a massive effect, just that one strand of activity.”

His appeal follows a spate of deadly Islamic State attacks in France, Belgium and Germany.

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